We already know that camel dung comes from camels. We already know that people leave footprints in the sand. But we don't know anything about any god, so the comparison does not work. The argument is a non sequitur.

The reason theists love this particular form of argument is because it appeals to their need for special coddling and their dislike of evolution (not to mention science in general).

Here's a humorous translation of what the theist argument really is.

Camel dung comes from camels
People leave footprints in the sand
The planets and stars and the entire universe is evidence that it all came about by magic.

"Fossil rabbits in the Precambrian"
~ J.B.S.Haldane, on being asked to falsify evolution.